Sorry Sarah, this guide is from when Pottermore had "interactive moments" that you could explore as you went through the story of each book. Now Pottermore is just the blog or whatever that you see today.

Hopefully, though unlikely, Pottermore will bring the moments back and this guide can be useful again.

I'm really really sad that they took the moments away, I didn't manage to finish the last two books =( It's highly unlikely they'll bring it back in the future since Rowling herself has stated that it's time to move on from them, but I did really enjoy the interactive-ness there and wish there were a way to finish it, even if I can't duel or brew anymore...